Field of the Invention
The invention relates to load break switches, and in particular, to a high voltage, load break switch having a solenoid release spring operating mechanism for opening and closing the switch.
Description of the Prior Art
When a circuit interrupter for an electric power distribution line trips in response to a fault condition, remotely operated disconnect switches, strategically placed in the feeders of the distribution circuit, can be opened or closed by an operator at a remote dispatch center to quickly isolate the faulted feeder and restore service to the unfaulted portions of the distribution line. It is desirable that the operating mechanisms of these disconnect switches include an energy storage device, such as a torsion spring, so that these switches can be operated without the aid of a low voltage source. For example, U.S. Pat. No. 3,789,172, issued Jan. 29, 1974, to Cole et al, discloses a solenoid release spring trip mechanism for actuating a disconnect switch having an energy storing spring which, when fully charged, has sufficient capacity for three successive operations without recharging. After each switch operation, the spring is fully recharged by a motor connected to a low voltage source.
One object of the invention is to provide a high voltage switch that can interrupt load current and is capable of closing in on a fault, having an operating mechanism which can be controlled from a remote source and which includes stored energy means for providing several opening and closing operations of the switch.
It is a related object of the invention to provide a switch lockout means for maintaining the load break switch in its opened position whenever the stored energy is depleted to a preset cutoff value, to assure that whenever the load break switch is closed, there is always sufficient stored energy to open the switch.
It is another object of the invention to provide a compact and lightweight load break switch, having a fast contact opening and closing speed uneffected by icing or corrosion caused by low temperature or contaminated atmospheric conditions.
A further object of the invention is to provide means for manually operating the load break switch, and manually recharging the energy storage means.
Yet another object of the invention is to provide a switch with sensing means for indicating the existance of a fault through the switch when interrogated by an operator at a remote location, as well as a switch that can remotely indicate its status.